Observing non-equilibrium state of transport through graphene channel at the nano-second time-scale

Mishra, Abhishek and Meersha, Adil and Raghavan, Srinivasan and Shrivastava, Mayank (2017) Observing non-equilibrium state of transport through graphene channel at the nano-second time-scale. In: APPLIED PHYSICS LETTERS, 111 (26).

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Abstract

Electrical performance of a graphene FET is drastically affected by electron-phonon inelastic scattering. At high electric fields, the out-of-equilibrium population of optical phonons equilibrates by emitting acoustic phonons, which dissipate the energy to heat sinks. The equilibration time of the process is governed by thermal diffusion time, which is few nano-seconds for a typical graphene FET. The nano-second time-scale of the process keeps it elusive to conventional steady-state or DC measurement systems. Here, we employ a time-domain reflectometry-based technique to electrically probe the device for few nano-seconds and investigate the non-equilibrium state. For the first time, the transient nature of electrical transport through graphene FET is revealed. A maximum change of 35% in current and 50% in contact resistance is recorded over a time span of 8 ns, while operating graphene FET at a current density of 1mA/mu m. The study highlights the role of intrinsic heating (scattering) in deciding metal-graphene contact resistance and transport through the graphene channel. Published by AIP Publishing.

Item Type:	Journal Article
Publication:	APPLIED PHYSICS LETTERS
Publisher:	10.1063/1.5006258
Additional Information:	Copy right for this article belongs to the AMER INST PHYSICS, 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA
Department/Centre:	Division of Electrical Sciences > Electronic Systems Engineering (Formerly Centre for Electronic Design & Technology)
Date Deposited:	20 Jan 2018 06:23
Last Modified:	20 Jan 2018 06:23
URI:	http://eprints.iisc.ac.in/id/eprint/58824

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